Sowmya Samudrala Venkatesiah

Background: Oral Submucous Fibrosis (OSMF) is a significant global oral health problem, particularly prevalent in India, with a high risk of progression to Oral Squamous Cell Carcinoma (OSCC). This study investigates the molecular mechanisms involved in the transformation of OSMF to OSCC using transcriptomic profiling. Methods: High-throughput RNA sequencing was performed on fresh de novo OSCC samples (n = 8) and OSMF derived OSCC using Illumina-compatible NEXTflex Rapid Directional RNA Sequencing. Normalization and differential gene expression analysis were conducted, and genes exhibiting an absolute log2 fold change of ≥2 with a co-variate-adjusted p-value ≤ 0.05 were identified as significant. Results: Upregulated genes were associated with cytokine and immune responses (ABRA, TTTY14, EIF1AY), cellular proliferation and apoptosis (LINC00314, RPS4Y1, SERPINA5, TRIM63, FABP7), and energy metabolism, indicating metabolic adaptations during malignant progression. Pathway analysis showed increased expression of TNNT1, TNNI1, MYL4, and ACTN3, implicating muscle development and embryonic pathways in OSMF transformation. Conversely, genes related to epithelial differentiation and keratinization (FLG, FLG2, HRNR, TCHH, KRT73), immune regulation and tumor suppression (HLA-G, UNC5D), and metabolic signaling were downregulated, reflecting loss of tissue integrity and immune control. Conclusions: OSMF-derived OSCC exhibits a distinct transcriptomic landscape compared with de novo OSCC, characterized by altered epithelial differentiation, immune modulation, and activation of developmental pathways. The observed gene dysregulation findings establish that OSCC developing in the background of OSMF is molecularly distinct from de novo OSCC, underscoring the biological impact of the pre-existing fibrotic milieu on tumor transcriptional architecture.

This review aims to understand the concept of oral cancer immunology through the notion of immune profiling, immunoediting and immunotherapy, and to gain knowledge regarding its application for the management of oral cancer patients. Oral cancer is an immunogenic tumor where the cells of the tumor microenvironment play an important role in tumorigenesis. Understanding the mechanism of these modulations can help design immunotherapeutic strategies in oral cancer patients. This article gives an overview of immunomodulation in the oral cancer tumor microenvironment, with concepts of immune profiling, immunoediting and immunotherapy. English literature searches via Google Scholar, Web of Science, EBSCO, Scopus, and PubMed database were performed with the key words immunology, tumor microenvironment, cells, cross talk, immune profiling, biomarkers, inflammation, gene expression, techniques, immunoediting, immunosurveillance, tumor escape, immunotherapy, immune checkpoint inhibitors, vaccines in cancer, oral cancer, and head and neck cancer. Original research articles, reviews, and case reports published from 2016–2021 (n = 81) were included to appraise different topics, and were discussed under the following subsections. Literature published on oral cancer immunology reveals that oral cancer immune profiling with appropriate markers and techniques and knowledge on immunoediting concepts can help design and play an effective role in immunotherapeutic management of oral cancer patients. An evaluation of oral cancer immunology helps to determine its role in tumorigenesis, and immunotherapy could be the emerging drift in the effective management of oral cancer.